Trampolines



Oct. 4, 1966 Filed May 18, 1965 N. S. HALL.

TRAMPOLINES FIG. 3

5 Sheets-Sheet 1 Oct. 4, 1966 N. s. HALL 3,276,544

TRAMPOLINES Filed May 18. 1965 5 Sheets-Sheet 5 INK/EN t United StatesPatent 3,276,544 TRAMPOLINES Nevil Siemers Hall, Flat 21, Highlands, 14Eezuidenhout St., Johannesburg, Transvaal, Republic of South AfricaFiled May 18, 1965, Ser. No. 456,758 Claims priority, applicationRepublic of outh Africa, Aug. 13, 1964, 2,236/64 2 Claims. (Cl.182--139) This invention relates to trampolines.

Trampolines are generally formed as Open frame structures having matssecured within the frames by means of resilient elements in the form ofcoiled tension springs or strong rubber or like bands stretched betweenthe frame and mat. The frames are either supported on suitable legs orlocated over an open pit.

It is very often necessary, particularly when such trampolines arelocated out of doors, to remove the mat and resilient elements from theframe when the apparatus is not in use to prevent theft or avoid thedeleterious effects of exposure on the mats and resilient elements.

This removal and re-attachment very often results in stretching of theresilient elements and even where periodical removal of the mat is notnecessary, the sustained tension in the mat and resilient elements maydamage these components and reduce the efiiiciency of the trampoline.

Apart from this the removal, attachment or replacement of eachindividual resilient element is a tedious and time consuming operation.

A known folding frame type of trampoline serves to reduce the tension ofthe resilient elements extending in one direction when the frame isfolded but the remaining elements extending in line with the fold remainunder full tension.

Also no types of trampolines known to applicant have provision foradjusting the tension of the resilient elements to compensate forstretching of these elements.

It is accordingly an object of this invention to provide a trampolineframe wherein the tension of most or all of the resilient elements canreadily be varied and which will facilitate removal and attachment ofthe mat to the frame.

It is a further object of the invention to provide a folding type oftrampoline embodying the above and additional advantageous features.

According to this invention there is provided a trampoline framecomprising a pair of side and a pair of end members connected to form agenerally rectangular open structure, a plurality of anchor meansembodied in each member for securing resilient mat supporting elementsthereto, the anchor means in at least one side and one end member beingmovable relative to the anchor means in the opposite side and endmembers respectively, while a mat is secured in the frame by the saidresilient elements.

A further feature of the invention provides for at least one side andone end member to be rotatable in relation to the remainder of the frameand for at least one side member to comprise hinged sections rotatablein unison when axially aligned.

Additional features of this invention will become ap parent from adescription of one illustrative embodiment thereof with reference to theaccompanying drawings in which:

FIG. I is an elevation of a folding trampoline,

FIG. 2 is a plan of FIG. 1,

FIG. 3 to are details,

FIG. 6 illustrates the method of attachment of the resilient matsupporting elements to the frame members,

FIG. 7 is an alternative form of hinge for the trampoline frame and FIG.8 is an elevation of the trampoline frame in the semi-folded condition.

Broadly, as shown in the drawings the frame 1 comprises a pair ofstraight tubular side members 2 connected to the ends of a pair ofU-shaped tubular end members 3 the centre portions 3A of which are alsostraight. The side members 2 are rotatable about their own axes, andeach consists of three sections 2A, 2B, and 2C connected together byhinges 4, 5 the arrangement being such that all three sections 2A, 2Band 2C and the corresponding hinges 4, 5 can rotate in unison when thesections are axially aligned.

The centre portions 3A of the U-shaped end members 3 are also rotatableand in both members 3 this is achieved by fitting the rotatable portions3A over spigots as more fully described hereinafter.

The frame carries a mat 6 secured by means of resilient mat supportingelements 7 attached to the mat 6 and anchored to perforations 8 in therotatable portions of the frame as is more clearly illustrated in FIG.6.

Thus, rotation of the rotatable portions of the frame will increase ordecrease the tension in the resilient elements 7 and the mat 6.

The frame 1 is supported on U'shaped legs 9 secured to the side members2 by means of sleeves 10 to allow rotation of the side members 2 whilesupported on the legs 9.

Rotation of each side member 2 is effected by a lever 11 attached to thecorresponding side member 2 by means of a cylindrical clamp 12 the leverif being adapted to engage a stop 13 on the legs 9.

Bracing stays 1d extend from the end members 3 are removably attached tothe legs 9.

Conveniently, the bracing stays I l serve the dual purpose of stays aswell as levers for effecting rotation of the rotatable centre portions3A of the end members 3. For this reason the stays T4 are adjustablysecured to these rotatable portions 3A, so that the tension of the mat 6may be varied with the stays 14 in the same operative position.

As shown in the drawings the two sides 2 of the frame 1 are formed fromtwo equal lengths of tubing which are rotatably fitted onto the twoU-shaped end members 3 of the frame 1, the side members 2 and endmembers 3 being of equal diameter. This is conveniently achieved bysecuring short lengths of tubing in the ends of the arms of the U-shapedend members 3 to form projecting spigots 15 over which the ends of thetwo side members 2 are rotatably fitted with the ends of the sidemembers 2 and end members 3 abutting or closely adjacent as isillustrated in FIG. 3.

With this construction the diameter of the frame 1 at any point is thesame so that there are no undesirable projections.

The end sections 2A and 20 of side members 2 adjacent the hinges i, 5are formed as separate sleeves it} rotatable on spigots 17 secured toand projecting from the bores of section 2A and 2C. The projectingportions of spigots 17 are slightly longer than the lengths of sleeves10 as is shown in FIG. 4.

The leaves 18 of hinges 5 are welded or otherwise secured to the end ofthe spigots 17 so that the leaves 18 project radially outwardly of thespigots 17 to form stops for sleeves 10, with the axes of the hinge pins19 located transversely to the axes of the spigots 17.

The other leaf 20 of each hinge 5 is welded or otherwise secured to thecentre section 23 of each side member 2 so that when the inner faces ofthe hinge leaves 18 and 29 abut all three sections 2A, 2B, 2(1 of theside m-em bers 2 are axially aligned.

The portions of the hinge leaves 18, Zil opposite the and hinge pins arecut away to correspond to the shape of the tubing of the frame 1wherever possible.

The hinges 4 are located in a similar manner between sections 2A and 2Bof each side member 2.

The hinge leaves of the hinges 4 are, however, of such a length that thecorresponding hinge pins 19 are located a distance from the outerperiphery of the tubing approximately equal to or greater than thediameter of the said tubing, so that these hinges 4 are longer than thehinges 5.

Alternatively, all the hinges may be in the form illustrated in FIG. 7with the members 21 connecting the two lengths of tubing made ofdifferent lengths for opposite ends of the frame.

The leg supports 9 are of substantially U-shape, the ends of eachsupport 9 being pivotally secured to lugs 22, which project from sleeves10.

The supports 9 can accordingly fold to lie closely adjacentcorrespondingly shaped end members 3 of the frame 1 but are normallyheld at an angle of approximately 45 to the frame by means of thebracing stays 14 which are secured to the centre portions 3A of theframe 1 and removably engage the supports 9.

The free ends of the bracing stays 14 are provided with hook formations23 adapted to engage the portions of the 'U-shaped supports 9 whichextend transverse to the length of the frame as shown in FIG. 5. Alocking pin 24 is carried in the stay 14 so as to be movable axiallytherein and the pin 24 serves to lock the end of the stay 14 to thesupport 9. Any other convenient form of bracing and removable lockarrangement may, however, be employed.

A single length of chain 25 (see FIG. 1) is passed over eachcorresponding leg of the opposite supports 9 so that the chains 25 lietowards the lower ends thereof. The U-shaped support 9 at one end of theframe has stops 26 for preventing the chain 25 from moving up or down inrelation to the legs although it can be freely threaded through thestops 26 and the other U-shaped support has similar stops 27 atcorresponding positions but from which the chain 25 can be removed.

Initially the chains 25 are passed through stops 26 and under stop 27and tautened, preferably by means of a turnbuckle 28 incorporated in thelength of each chain 25, so that even with the bracing stays 14 removed,the chains 25 maintain the supports 9 substantially in the operativeposition. When it is desired to fold the supports 9, the chains 25 arelifted over the one set of stops 27, and, as the one or other set ofsupports 9 are folded, the chains 25 are allowed to slide up thesupports 9 towards the hinges 5.

The effect of this would be that the chains 25 are always maintained ina comparatively taut condition.

The supports 9 or chains 25 will preferably be provided with aprotective sheath of resilient material (not shown) such as rubber or asynthetic resin where the chains 25 are likely to rub. The supports 9may also be provided with similar sheaths 29 at their lower extremitiesto serve as feet for the apparatus.

The rotatable tubular members of the frame 1 are perforated at intervals(see FIG. 6) so that with the hinge leaves of hinges 4 and projectingdownwardly, the perforations 8 in the sides 2 and end members 3 of theframe 1 are directed towards the inside of the frame 1.

The resilient mat supporting elements in this example are lengths ofrubber bands '7 folded double and having wire hooks 30 secured to theirfree ends. The opposite ends of the rubber bands are secured to theedges of the trampoline mat 6 at spaced intervals corresponding to theintervals between the perforations 8 in the frame 1.

The mat 6 is secured within the frame 1 by rotating the side members 2of the frame so that the perforations 8 are located at the outside ofthese members and the rubber bands 7 are passed over these members andthe hooks .30 passed through the perforations 8.

It will be appreciated that with the perforations 8 located at theoutside of the side members 2 of the frame the leaves of the hinges 4, 5of these members project upwardly.

The lever arm 11, having a handle 31, is used as a locking mechanism forpreventing rotation of the side members and is pivotally secured to thelug 32 welded or otherwise secured to both side members 2 of the frame 1by means of the cylindrical clamps 12. A stop 13 is provided on twoopposite legs of the one support 9 and these stops are shaped so thatthe lever arm 11 may be engaged therein to prevent rotation of the sidemembers 2. In the locked position the leaves of the hinges 4, 5 projectdownwardly so that in order to secure the side members 2 againstrotation it is necessary to rotate the side members and this isfacilitated by means of the lever arm 11.

This rotation of the side members 2 and perforations 8 throughapproximately serves to tension the resilient elements 7 which are of alength that will ensure that in this position they are sufficientlytensioned while in the unsecured position of the side members 2 thehooks 30 can be inserted into the perforations 8 without difficulty.

However, since this movement between the two positions of the rotatableside members 2 may not be correct once the resilient elements havestretched or for any other reason, the angular disposition of each leverarm 11 is made adjustable relative to the side members 2 by means of thecylindrical clamps 12 which may be secured in an appropriate positionrelative to the side members 2.

With the mat 6 secured within the frame 1 and with the frame erected,the tension in the resilient elements 7 tends to maintain the frame 1 inthe erected condition since the hinge pins of hinges 4 and 5 are locatedbelow the centre of the frame.

To fold the apparatus both lever arms 11 are released from the stops 13of the supports 9 and allowed to rotate upwardly under action of theresilient elements 7 so that hinge pins 19 of hinges 4, 5 are above theframe. The bracing stay 14 on the end of the frame nearest the shorterhinges 5 is then disengaged from the corresponding U-shaped supports 9which is then folded flush against the frame section 2C which latter isthen folded over centre section 2B (see FIG. 8). The same procedure isthen followed with the other support 9 which, by virtue of the longerhinge 4, may be folded together with section 2A over the previouslyfolded portion of the assembly.

Since the hinges should project vertically to permit the sections of theframe to fold, stops (not shown) may be located to arrest rotation ofthe side members 2 when the hinges arrive at the correct position.

As described above the chain 25 around one leg of each support 9 isremoved from the stops 27 before folding either support 9.

The apparatus is thus folded into a neat assembly which is easy totransport and requires little storage space and the mat 6 and resilientelements 7 are relieved of tension in this condition.

To erect the apparatus for use the reverse procedure is followed.

It will be appreciated that the rotating side members 2 of the frame 1do not form the only adjustable resilient element locating means sinceadjustment of the position of bracing stays 14 relative to sections 3Aprovides for adjustment of the operative tension of the resilientelements at the ends of the frame.

The tension in the end resilient elements 7 is, however, released whendisengaging the stays 14 from the supports 9 and swinging the staysoutwardly to lie in line with the length of and within the frame.

It is advantageous to extend the length of pipe of reduced diameterforming the supporting spigots 15 for the side members 2 around thebends to form similar spigots for the rotating end members 3A and inthis Way strengthen the frame at the bends.

It will be appreciated that various modifications may be made to theexample above described without departing from the scope of theinvention and while the invention has been described as applied to afolding frame the use of rotatable framing members for varying thetension of the resilient elements could also be applied to a rigidtrampoline frame structure.

What I claim as new and desire to secure by Letters Patent is:

1. A trampoline comprising a generally rectangular open structure, endmembers and oppositely disposed assemblies of side sections forming partof said structure, hinges connecting said side sections together,mountings for the end members allowing rotation thereof about their ownaxes, mountings for the assemblies of side sections allowing rotation ofeach assembly with the sections forming each assembly axially aligned, apair of sleeves on each assembly of side sections, supporting legssecured to said sleeves, braces rigidly secured to said end members andprojecting generally radially therefrom, means for detachably securingthe braces to the legs and anchor means embodied in the end members andside sections.

2. A trampoline in accordance with claim 1 including a locking armhinged to a side section of each assembly and a step on thecorresponding legs detachably engageable by the locking arm.

References Cited by the Examiner UNITED STATES PATENTS 952,871 3/1910Browder 182139 2,430,714 11/1947 Geer 182139 2,809,383 10/1957 Fenner182-439 2,858,551 11/1958 Sidlinger 182-139 3,226,861 1/1966 Bird160-378 20 REINALDO P. MACHADO, Primary Examiner.

1. A TRAMPOLINE COMPRISING A GENERALLY RECTANGULAR OPEN STRUCTURE, ENDMEMBERS AND OPPOSITELY DISPOSED ASSEMBLIES OF SIDE SECTIONS FORMING PARTOF SAID STRUCTURE, HINGES CONNECTING SAID SIDE SECTINS TOGETHER,MOUNTINGS FOR THE END MEMBERS ALLOWING ROTATION THEREOF ABOUT THEIR OWNAXES, MOUNTINGS FOR THE ASSEMBLIES OF SIDE SECTIONS ALLOWING ROTATION OREACH ASSEMBLY WITH THE SECTIONS FORMING EACH ASSEMBLY AXIALLY ALIGNED, APAIR OF SLEEVES ON EACH ASSEMBLY OF SIDE SECTIONS, SUPPORTING LEGSSECURED TO SAID SLEEVES, BRACES RIGIDLY SECURED TO SAID END MEMBERS ANDPROJECTING GENERALLY RADIALLY THEREFROM, MEANS FOR DETACHABLY SECURINGTHE BRACES TO THE LEGS AND ANCHOR MEANS EMBODIES IN THE END MEMBERS ANDSIDE SECTIONS.